I tried looking this up, but all I could find were Yahoo Q&As and I trust you more than them! I bought a scratching toy for Junie that is really meant for cats, but I think she'll like it, too. It comes with a small baggy of catnip. The directions say to sprinkle a bit over the scratching part of the toy to attract cats to scratch it. The pieces of catnip are dried and crumbled, so they're very small. If she ate some, would it be bad? Or is it okay for bunnies? She can still use the scratching bit, but it might be a fun treat to have the catnip on it, too.

I got my information from Rabbit Health in the 21st Century, page 166. It also says, which I should have mentioned, not to feed rabbits [or maybe any other animal] the seeds. Seeds wouldn't be in any catnip you buy, but with growing plants, just don't use the seed heads.

If you don't have plants, if your rabbit likes dried catnip, you could use catnip teabags: tear off string & remove staple, of course. Your rabbit may enjoy playing with &/or eating the bag & it's ok if they do, though a bit messy with dried catnip all over until they eat it up.